Which oil to choose?

In order to answer this question, let us take a look at what are the different types of engine oils and how are the properties of one brand of oil different from another. One also has to keep in mind the conditions in which the engines are used when choosing its oil.

Synthetic vs. Conventional oil

Conventional / Mineral oils are based on petroleum oil which is refined from crude oil. They have chemically weak properties and deteriorate soon during normal engine operation.

Synthetic oils are refined and produced from stronger chemicals that can keep their properties for longer during normal and severe engine operation. Therefore, synthetic oil has long drain intervals compared to mineral oils.

Engine oil Grading

Engine oil has basically two grading systems; one is based on quality and performance called the API Grading and the second is based on the viscosity of the oil called SAE Grading.

1. Quality/Performance Grading (API GRADING)

2. Viscosity Grading (SAE GRADING)

API GRADING (Performance grading)

API (American Petroleum Institute) oil grading is based on the results and performance of many tests and trails of the engine oil.

Multi-grade oils have labels for both extreme cold and hot conditions. For example, the oil which has a label like 10W40 is called multi-grade engine oil.

Mentioned below is SAE J300 table for Viscosity Grading

SAE and ISO Viscosity Tables

SAE Viscosity Grades for Engine Oils SAE J300

SAE Oil Viscosity Grade

Low Temperature º C Cranking Viscosity (mPa.s) Max (CCS)

Low Temperature º C Pumping Viscosity(mPa.s) Max (MRV)

Viscosity (mm ² /s) at 100 º C Min

Viscosity (mm ² /s) at 100 º C Max

High Shear Rate Viscosity (mPa.s) at 150 º C Min

0W

6200 @ -35

60000 @ -40

3.8

–

–

5W

6600 @ -30

60000 @ -35

3.8

–

–

10W

7000 @ -25

60000 @ -30

4.1

–

–

15W

7000 @ -20

60000 @ -25

5.6

–

–

20W

9500 @ -15

60000 @ -20

5.6

–

–

25W

13000 @ -10

60000 @ -15

9.3

–

–

20

–

–

5.6

9.3

2.6

30

–

–

9.3

12.5

2.9

40

–

–

12.5

16.3

2.9 (0W – 10W)

40

–

–

12.5

16.3

3.7 (15W – 25W)

50

–

–

16.3

21.9

3.7

60

–

–

21.9

26.1

3.7

Driving Conditions in Pakistan

Some types of car operations are more severe than others, placing greater demands on the motor oil and calling for more frequent oil changes. For this reason, car manufacturers give two recommendations for oil changes in their owner’s manuals.

Standard Service

Standard conditions are generally where a vehicle drives more than 15,000 km with out short distance, and congested & traffic jam condition where stop and go is very rapid. And there are few periods of long Idling (car keep started on stationary position).

Severe Service

This service is applicable where city traffic has no flow systematically, short trips drive where stop and go condition prevails, off road drive conditions, irregular loading conditions, to many long Idling etc.

kashif masood

its good but can more if pic mention with information i mean to say that ur product with that tag

faizan

what typ of SAE grade shld we use in pkistn n whn the engne is 100,000 km old.

munib

I live in Karachi. According to above chart KHI engines (with avg KM on meter , say 25000km to 50000km ) should use 20-50 because temperature in KHI hardly goes below even during winter (exceptions apart)